Novel magnetic core and coil structure for probe type closed-loop fluxgate sensor

Abstract

The invention belongs to the technical field of fluxgate sensors, and relates to a novel magnetic core and coil structure for a probe type closed-loop fluxgate sensor. The structure comprises a main magnetic core of an annular magnetic core, a magnetic probe part embedded on the main magnetic core and a compensation coil wound on the main magnetic core. The main magnetic core is made of ferrite materials with low cost, and the magnetic probe component is composed of a magnetic probe framework, a magnetic tape material structure and a magnetic probe coil. The magnetic probe framework is annular, the magnetic tape material structure is composed of a magnetic material coiled material and an adhesive tape, the coiled material is a nanocrystalline material, and the adhesive tape is used for fixing the magnetic tape material on the framework. The main magnetic core is provided with a U-shaped annular groove, and the magnetic probe part is embedded in the U-shaped annular groove. The structural design aims to overcome the defects of a magnetic core and a coil structure of a traditional closed-loop fluxgate sensor, the cost is reduced, and meanwhile, the performance such as sensitivity, excitation frequency and bandwidth is kept or improved.

Description

Technical Field

[0001] The present invention relates to a fluxgate sensor, and more particularly to a novel magnetic core and coil structure for a probe type closed loop fluxgate sensor. Background Art

[0002] Fluxgate technology is often used to make sensors for current detection or leakage current detection. This technology is divided into open-loop fluxgate and closed-loop fluxgate. The closed-loop fluxgate technology has some advantages that the open-loop fluxgate does not have, such as high precision, high linearity, low temperature drift, low zero drift, high bandwidth, etc. Its stability is often better than that of the open-loop fluxgate. The core and coil structure of the closed-loop fluxgate is also often much more complicated than that of the open-loop fluxgate.

[0003] The existing closed-loop fluxgate technology uses a variety of magnetic core and coil structures, but they are basically inseparable from two coils, one is the excitation coil and the other is the compensation coil. The only difference is the design in terms of the structure of the core coil or the material selection of the core.

[0004] In terms of structure, traditional closed-loop fluxgate solutions often use a pure toroidal magnetic core to wind the excitation coil and the compensation coil, or a combination of a special-shaped spliced ​​magnetic core and a magnetic probe. Both forms have their own advantages and disadvantages: The advantages of winding the coil directly on a pure annular magnetic core are relatively simple structure and process, no air gap, and high sensitivity. The disadvantages are relatively large coil inductance, low excitation frequency, and low bandwidth. The advantage of using a combination of special-shaped spliced ​​magnetic cores and magnetic probes is low magnetic probe inductance, high excitation frequency, and high bandwidth. The disadvantages are relatively complex structure and process, and high cost.

[0005] In terms of the selection of core materials, no matter which traditional solution is used, Permalloy or nanocrystals and other materials are generally used as the main core, which are relatively expensive. Summary of the invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a new type of magnetic core and coil structure to overcome the shortcomings of the traditional solution, and in terms of material selection, a lower-cost ferrite is selected as the magnetic core, thereby further reducing the cost of the solution.

[0007] To achieve the above object, the present invention provides the following technical solutions: A new magnetic core and coil structure for a probe-type closed-loop fluxgate sensor includes a main magnetic core, a magnetic probe component and a compensation coil. The main magnetic core is a ring-shaped magnetic core, the magnetic probe component is a wound magnetic probe coil assembly and is embedded in the main magnetic core, and the compensation coil is wound on the main magnetic core.

[0008] Furthermore, the main magnetic core is made of ferrite.

[0009] Furthermore, the magnetic probe component includes a magnetic probe frame, a magnetic tape structure and a magnetic probe coil. The magnetic tape structure is attached to the magnetic probe frame, and the magnetic probe coil is wound on the magnetic probe frame and the magnetic tape structure.

[0010] Furthermore, the magnetic probe skeleton is ring-shaped, and the magnetic tape structure includes a magnetic tape, which is a coil of magnetic material. The magnetic tape is connected end to end and is attached to the magnetic probe skeleton in a ring-shaped shape.

[0011] Furthermore, the magnetic tape structure also includes an adhesive tape, which is attached to the magnetic tape, and the magnetic material is attached to the magnetic probe frame through the adhesive tape.

[0012] Furthermore, the magnetic tape can be attached to the magnetic probe frame by glue.

[0013] Furthermore, the magnetic material coil is nanocrystalline.

[0014] Furthermore, a U-shaped ring groove is provided on the main magnetic core, and the magnetic probe component is embedded in the U-shaped ring groove.

[0015] By adopting the above technical solution, the beneficial effects of the present invention are: 1. Cost reduction: By selecting ferrite as the main magnetic core material, the present invention significantly reduces the cost compared with traditional Permalloy or nanocrystalline materials.

[0016] 2. Performance improvement: Although a relatively low-cost ferrite material is used, under the novel structure designed by the present invention, the performance of the ferrite is similar to that of the traditional Permalloy or nanocrystal, thus maintaining the high performance of the sensor.

[0017] 3. Structural optimization: The annular structure design of the magnetic probe component provides better sensitivity and stability compared to traditional rod-shaped magnetic probes.

[0018] 4. No air gap design: The annular structure of the magnetic probe has no air gap, which makes the magnetic induction more uniform and less susceptible to interference, thus improving the accuracy and reliability of the sensor.

[0019] 5. Improved material utilization: The magnetic tape structure uses extremely thin magnetic material coils, which consumes less material and is low in cost, while also reducing the inductance of the excitation coil.

[0020] 6. Improved excitation frequency and bandwidth: Due to the low sensitivity of the magnetic probe, the excitation frequency can be higher and the bandwidth can be higher, which improves the response speed and working range of the sensor.

[0021] 7. Simplified process: Compared with the traditional combination of special-shaped spliced ​​magnetic cores and magnetic probes, the structure and process of the present invention are relatively simple and easy to manufacture and maintain.

[0022] 8. High stability and uniformity: The design of the annular magnetic probe makes the induction of the magnetic core more uniform in current detection applications, improving the stability of the sensor and the accuracy of measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a diagrammatic representation of the overall structure of the novel magnetic core and coil structure described in the present invention.

[0024] Figure 2 It is a structural schematic diagram of the main magnetic core and the magnetic probe in the novel magnetic core and coil structure described in the present invention.

[0025] Figure 3 This is a schematic diagram of the component decomposition structure of the magnetic probe described in the present invention.

[0026] Figure 4 It is a schematic diagram of the magnetic tape structure in the magnetic probe described in the present invention.

[0027] Figure 5 It is a structural schematic diagram of the unfolded magnetic tape structure in the magnetic probe described in the present invention.

[0028] Reference numerals: main magnetic core 1 , compensation coil 2 , magnetic probe component 3 , magnetic probe skeleton 31 , magnetic tape structure 32 , magnetic probe coil 33 , magnetic tape 321 , adhesive tape 322 . DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0031] like Figure 1 As shown, the novel magnetic core and coil structure proposed in the present invention mainly includes three major components: a main magnetic core 1, a compensation coil 2 on the main magnetic core, and a magnetic probe component 3 embedded in the U-shaped ring groove of the main magnetic core.

[0032] The magnetic probe component 3 is a wound magnetic probe coil assembly, which is inserted into the U-shaped ring groove of the main magnetic core 1, and then the compensation coil 2 is wound on the main magnetic core 1, thus forming the new magnetic core and coil structure of the present invention.

[0033] like Figure 2 As shown, Figure 1 The magnetic probe can be taken out from the U-shaped groove of the main magnetic core 1 by removing the middle compensation coil 2. The material of the main magnetic core 1 is a relatively cheap ferrite. Compared with the traditional solution of using Permalloy or nanocrystal as the main magnetic core, ferrite has a lower cost, and under the structural form designed by the present invention, the performance of ferrite is similar to that of traditional Permalloy or nanocrystal.

[0034] like Figure 3 As shown, the magnetic probe component 3 includes a magnetic probe skeleton 31 , a magnetic tape structure 32 and a magnetic probe coil 33 .

[0035] like Figure 4 As shown, Figure 3 By removing the magnetic probe coil in the figure, it can be seen that the magnetic tape structure 32 is attached to the magnetic probe skeleton 31 and surrounds it.

[0036] like Figure 5 As shown, this is a composition diagram of the magnetic tape structure 32, which is divided into a magnetic tape 321 and an adhesive tape 322. The magnetic tape is an extremely thin coil of magnetic material, and the coil material is nanocrystalline.

[0037] Compared with the traditional solution of winding the excitation coil on a pure toroidal magnetic core, the magnetic tape material uses very little material and has very low cost. At the same time, it reduces the inductance of the excitation coil, has a high excitation frequency, and can achieve a higher bandwidth.

[0038] Compared with another traditional solution, that is, using a special-shaped spliced ​​magnetic core plus a magnetic probe, the form of the magnetic probe has been improved. The traditional solution is often a short rod-shaped magnetic probe with a length of about 10 to 20 mm and a straight strip shape, embedded in the middle of the special-shaped magnetic core. The present invention lengthens the magnetic material of the magnetic probe and rolls it into a ring through tape coating. The magnetic tape 321 is connected end to end and firmly adhered with tape 322. The structure of the rod-shaped magnetic probe is optimized into a ring-shaped magnetic probe, which has better sensitivity, and the air gap-free ring structure is more stable. When used in current detection applications, the induction of the magnetic core is more uniform and less susceptible to interference.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor, characterized in that: include The main magnetic core is a toroidal magnetic core. The magnetic probe component is a wound magnetic probe coil assembly embedded in the main magnetic core. The compensation coil is wound on the main magnetic core.

2. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor according to claim 1, characterized in that: The main magnetic core is made of ferrite.

3. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor according to claim 2, characterized in that: The magnetic probe component comprises a magnetic probe frame, a magnetic tape structure and a magnetic probe coil. The magnetic tape structure is attached to the magnetic probe frame, and the magnetic probe coil is wound on the magnetic probe frame and the magnetic tape structure.

4. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor according to claim 3, characterized in that: The magnetic probe frame is annular, and the magnetic tape structure comprises magnetic tape, which is a coil of magnetic material. The magnetic tape is connected end to end and is attached to the magnetic probe frame in an annular shape.

5. A novel magnetic core and coil structure for a probe-type closed-loop fluxgate sensor according to claim 4, characterized in that: The magnetic tape structure also includes an adhesive tape, which is attached to the magnetic tape and the magnetic material is attached to the magnetic probe frame through the adhesive tape.

6. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor according to claim 4, characterized in that: The magnetic tape can be attached to the magnetic probe frame by glue.

7. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor according to claim 5 or 6, characterized in that: The magnetic material coil is nanocrystalline.

8. A novel magnetic core and coil structure for a probe type closed loop fluxgate sensor according to claim 2 or 4, characterized in that: The main magnetic core is provided with a U-shaped ring groove, and the magnetic probe component is embedded in the U-shaped ring groove.

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